Saturday, November 21, 2020

Loss of Control in Flight: AgustaWestland AW109S Grand, N11NM; fatal accident occurred June 28, 2019 at Brainerd Lakes Regional Airport (KBRD), Crow Wing County, Minnesota

Timothy Alan McDonald
~

Deb Schott















The National Transportation Safety Board traveled to the scene of this accident. 

Additional Participating Entities:
Federal Aviation Administration / Flight Standards District Office; Minneapolis, Minnesota
Federal Aviation Administration Rotorcraft Directorate; Fort Worth, Texas
North Memorial Health; Crystal, Minnesota
Transportation Safety Board of Canada; Ottawa, Ontario
Italian Civil Aviation Authority; San Marino, FN

Investigation Docket - National Transportation Safety Board:
https://app.ntsb.gov/pdf

Location: Brainerd, Minnesota
Accident Number: CEN19FA185
Date & Time: June 28, 2019, 00:40 Local
Registration: N11NM
Aircraft: Agusta A109 
Aircraft Damage: Substantial
Defining Event: Loss of control in flight 
Injuries: 2 Fatal, 1 Serious
Flight Conducted Under:

Analysis

The crew of the helicopter air ambulance flight was approaching the airport for landing in dark night instrument meteorological conditions (IMC) after delivering a patient to the hospital. The reported weather conditions about the time the pilot initiated the instrument landing system (ILS) approach included 1/2-mile visibility with haze, which then deteriorated to 1/4 mile, which was within the operator's approved visibility approach minimums. The paramedic onboard reported that he saw the runway environment through a thin layer of fog as the helicopter descended toward the decision height (DH) of 200 ft above ground level during the approach.

After descending below the DH, with a power setting below 30% torque, the helicopter's pitch attitude increased from -3° (nose-down) to +20° (nose-up), its airspeed decreased from 100 to 50 knots, and the pilot declared a missed approach, likely due to a loss of visual contact with the runway environment. The pilot's increased collective input and the helicopter's decreasing airspeed resulted in an increase in torque, and the helicopter entered a right rotational yaw that accelerated into a spin. The helicopter subsequently impacted terrain near the runway.

The dark night conditions at the rural airport resulted in little to no visual references during the pilot's transition to landing and the attempted missed approach. It is likely that the pilot became spatially disoriented, which led to the excessive pitch attitude, slow airspeed, his failure to recognize and arrest the right yaw, and the subsequent loss of control.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot's spatial disorientation during an instrument approach in dark night instrument meteorological conditions, which resulted in a loss of control and subsequent impact with terrain.

Findings

Personnel issues Spatial disorientation - Pilot
Personnel issues Aircraft control - Pilot
Environmental issues Dark - Effect on operation
Environmental issues Fog - Effect on operation
Aircraft Airspeed - Not attained/maintained

Factual Information

History of Flight

Approach-IFR missed approach Loss of control in flight (Defining event)

On June 28, 2019, about 0040 central daylight time, an Agusta Spa A109S helicopter, N11NM, was substantially damaged when it was involved in an accident at Brainerd Lakes Regional Airport (BRD), near Brainerd Lakes, Minnesota. The pilot and flight nurse were fatally injured, and the flight paramedic was seriously injured. The helicopter was operated by North Memorial Healthcare as a Title 14 Code of Federal Regulations Part 135 helicopter air ambulance flight.

The flight was returning to BRD after delivering a patient to North Memorial Heliport (MY77), Robbinsdale, Minnesota. An onboard Appareo Vision 1000 device recorded flight data, cockpit imagery, and audio of the flight. The helicopter departed MY77 at 2348, and the pilot received an instrument flight rules clearance from air traffic control (ATC) to climb to 6,000 ft mean sea level (msl) and fly direct to BRD.

At 2356, while holding an iPad, the pilot stated on intercom to the paramedic and/or flight nurse that visibility at BRD was "1 mile, looks good." The pilot requested the instrument landing system runway 23 (ILS RWY 23) approach and informed the controller that he had obtained the current weather at BRD.

At 0028, the pilot selected the BRD automated surface observing system (ASOS) frequency. The ASOS transmission included a ceiling of 200 ft above ground level (agl) and 1/4-mile visibility with fog. The controller cleared the helicopter for the ILS RWY 23 approach. Shortly thereafter, the ASOS transmitted weather included 1/2-mile visibility with haze, and the pilot stated "awesome, 1/2 we're
legal" on the intercom. The pilot subsequently activated the runway lights.

At 0034:35, the helicopter began a descent on the ILS glideslope with the autopilot coupled. About 5 seconds later, the pilot appeared to turn on the helicopter's landing light and/or search light.

At 0036:30, the helicopter passed the final approach fix (5.3 miles from Runway 23) at 93 knots.

At 0036:37, the ASOS-transmitted weather included 1/4-mile visibility with haze and a sky condition of 200 ft vertical visibility.

After arriving at the ILS decision height, the pilot selected the altitude hold mode on the flight director and about 1 second later, decoupled the autopilot (pitch and roll steering modes). The radar altimeter read 130 ft agl. Over the next 14 seconds, with a power setting below 30% torque, the helicopter's pitch increased from -3° (nose-down) to +20° (nose-up) and the radar altimeter increased to 230 ft agl. As airspeed decreased below 50 knots, the pilot selected vertical speed, and heading modes on the flight director. The helicopter's power increased rapidly through 40% torque and the airspeed decreased through 25 knots. Based on a GPS groundspeed of 40 knots, the airborne tailwind was about 15 knots.

At 0039:38, the pilot announced a go-around. The helicopter's power increased past 80% torque, and the airspeed was 0 knots. The flight instruments indicated that the helicopter had entered a right rotational yaw and the radar altimeter read 300 ft agl. The helicopter's right yaw continued to increase; the power setting rose above 110% torque and the airspeed remained near 0 knots.

The last recorded information, at 0039:57, indicated that the helicopter was about 100 ft agl. The power setting was below 30% torque and the pilot had selected the "ALT" (altitude hold) button on the flight director.

Recorded images of the approach and attempted go-around did not provide a view of the runway environment or weather conditions.

Following the accident, the flight paramedic (seated in the left forward seat) recalled that the runway lights and surface were visible below a thin fog layer during the approach. As the helicopter approached the runway, he noticed clouds to the side and recalled the pilot stating that the weather conditions were foggy and that a go-around was needed. The helicopter subsequently spun to the right and impacted the ground.

Pilot Information

Certificate: Commercial 
Age: 44,Male
Airplane Rating(s): None
Seat Occupied: Right
Other Aircraft Rating(s): Helicopter
Restraint Used: 4-point
Instrument Rating(s): Helicopter
Second Pilot Present:
Instructor Rating(s): None 
Toxicology Performed: Yes
Medical Certification: Class 2 Without waivers/limitations
Last FAA Medical Exam: January 10, 2019
Occupational Pilot: Yes 
Last Flight Review or Equivalent: March 12, 2019
Flight Time: 3376 hours (Total, all aircraft), 533 hours (Total, this make and model), 2294 hours (Pilot In Command, all aircraft), 38 hours (Last 90 days, all aircraft), 11 hours (Last 30 days, all aircraft), 0 hours (Last 24 hours, all aircraft)

Passenger Information

Certificate: None
Age: 58,Female
Airplane Rating(s): None 
Seat Occupied: Rear
Other Aircraft Rating(s): None 
Restraint Used: 4-point
Instrument Rating(s): None
Second Pilot Present:
Instructor Rating(s): None 
Toxicology Performed: No
Medical Certification: None
Last FAA Medical Exam:
Occupational Pilot: No
Last Flight Review or Equivalent:
Flight Time:

Passenger Information
Certificate: None 
Age: 42,Male
Airplane Rating(s): None 
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 4-point
Instrument Rating(s): None
Second Pilot Present:
Instructor Rating(s): None 
Toxicology Performed: No
Medical Certification: None 
Last FAA Medical Exam:
Occupational Pilot: No
Last Flight Review or Equivalent:
Flight Time:

The pilot's most recent Part 135 competency/proficiency check occurred on March 12, 2019.

During the 90 days before the accident, the pilot logged 27 landings at night, 16 instrument approaches, 1 flight hour of actual instrument time, and 57 hours of simulated instrument time. The pilot's total actual instrument time flown was 41 hours.

Aircraft and Owner/Operator Information

Aircraft Make: Agusta
Registration: N11NM
Model/Series: A109 S
Aircraft Category: Helicopter
Year of Manufacture: 2008 
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 22075
Landing Gear Type: Retractable - Tricycle
Seats: 5
Date/Type of Last Inspection: June 18, 2019 AAIP 
Certified Max Gross Wt.: 7000 lbs
Time Since Last Inspection: 
Engines: 2 Turbo shaft
Airframe Total Time: 2723 Hrs at time of accident 
Engine Manufacturer: Pratt & Whitney Canada
ELT: Not installed 
Engine Model/Series: PW207C
Registered Owner: 
Rated Power: 750 Horsepower
Operator:
Operating Certificate(s) Held: On-demand air taxi (135)

The helicopter was equipped with a 2-axis autopilot for lateral (roll) and longitudinal (pitch) control. The autopilot provided for limited yaw dampening, but no yaw control. Minimum airspeed to comply with IFR handling quality requirements for the helicopter was 55 knots.

Meteorological Information and Flight Plan

Conditions at Accident Site: Instrument (IMC) 
Condition of Light: Night/dark
Observation Facility, Elevation: KBRD,1221 ft msl
Distance from Accident Site: 0 Nautical Miles
Observation Time: 00:18 Local 
Direction from Accident Site: 312°
Lowest Cloud Condition: Unknown 
Visibility: 0.25 miles
Lowest Ceiling: Broken / 200 ft AGL
Visibility (RVR):
Wind Speed/Gusts: 4 knots / 
Turbulence Type Forecast/Actual: None / None
Wind Direction: 50° 
Turbulence Severity Forecast/Actual: N/A / Light
Altimeter Setting: 30.07 inches Hg 
Temperature/Dew Point: 19°C / 16°C
Precipitation and Obscuration: Moderate - None - Haze
Departure Point: Robbinsdale, MN (MY77)
Type of Flight Plan Filed: IFR
Destination: Brainerd, MN (BRD ) 
Type of Clearance: IFR
Departure Time: 23:48 Local
Type of Airspace: Class E

BRD was located in a rural area with few ground lights, and there was no moon illumination at the time of the accident. Airport personnel stated that several lakes near BRD would often generate patchy fog and visibility could vary significantly at different locations on the airport.

The BRD ASOS was located about 600 ft left of runway 23 and about 1,200 ft from the runway threshold. BRD did not have equipment to measure runway visual range (RVR) for the touchdown zone.

At the time of the accident, the ASOS reported wind from 040° at 5 knots, 1/4 statute mile visibility, haze, vertical visibility of 200 ft agl, temperature of 19°C and a dew point temperature of 17°C.

The terminal aerodrome forecast (TAF) valid for BRD about the accident time included wind from 020° at 4 knots, 1 1/2 statute miles visibility, haze, and a clear sky. An AIRMET advisory for instrument flight rules (IFR) conditions was valid at the accident time.

Airport Information

Airport: Brainerd Lakes Rgnl BRD 
Runway Surface Type: Concrete
Airport Elevation: 1232 ft msl
Runway Surface Condition: Dry
Runway Used: 23 
IFR Approach: ILS
Runway Length/Width: 6512 ft / 150 ft 
VFR Approach/Landing: None

Wreckage and Impact Information

Crew Injuries: 2 Fatal, 1 Serious
Aircraft Damage: Substantial
Passenger Injuries:
Aircraft Fire: None
Ground Injuries:
Aircraft Explosion: None
Total Injuries: 2 Fatal, 1
Serious Latitude, Longitude: 46.403331,-94.128334

The helicopter impacted a grassy area south of runway 23 and came to rest upright and nearly intact on a heading of 074°. The main fuselage and tail boom exhibited crushing consistent with a high-velocity vertical descent and impact. The helicopter was upright and nearly intact, with no movement from the initial impact point. There was no evidence of a postcrash fire. The ground adjacent
to the wreckage was soaked with fuel and the smell of fuel was present at the accident site.

Examination of the helicopter and review of recorded flight information revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

Additional Information

Spatial Disorientation

The FAA's Airplane Flying Handbook (FAA-H-8083-3B) describes some hazards associated with flying when the ground or horizon are obscured. The handbook states, in part, the following:

The vestibular sense (motion sensing by the inner ear) in particular can and will confuse the pilot. Because of inertia, the sensory areas of the inner ear cannot detect slight changes in airplane attitude, nor can they accurately sense attitude changes that occur at a uniform rate over a period of time. On the other hand, false sensations are often generated, leading the pilot to believe the attitude of the airplane has changed when, in fact, it has not. These false sensations result in the pilot experiencing spatial
disorientation.

FAA Instrument Approach Guidance

FAA guidance for helicopter instrument approaches allows a reduction of the Category A visibility by half, but in no case less than 1⁄4 statute mile or 1,200 ft runway visual range (RVR). The approach can be initiated at any speed up to the highest approach category authorized; however, the speed on the final approach segment must be reduced to the Category A speed of less than 90 knots before the missed approach point in order to apply the visibility reduction.

Operator Training and Guidance

The operator's flight training and currency programs were all conducted inflight, as the only A109 simulator was based in Italy. Following a September 2016 accident that involved a loss of control during a missed approach in night IMC conditions, the operator started construction of a flight training device (FTD) for instrument procedures using an actual A109S cockpit. The FTD was not yet certified or in use at the time of the accident.

Following the accident, the operator increased the minimum weather conditions required for their pilots to conduct an instrument approach to a cloud ceiling of 400 ft agl and 1 mile visibility.

Medical and Pathological Information

An autopsy was performed on the pilot and flight nurse by the Ramsey County Medical Examiner, St. Paul, Minnesota. The cause of death was multiple traumatic injuries. 

The Federal Aviation Administration (FAA) Forensic Sciences Laboratory performed toxicological testing on the pilot. The tests were negative for all screened-for drugs, carbon monoxide, and alcohol.

Survival Aspects

The FAA Civil Aerospace Medical Institute (CAMI) reviewed the helicopter's seats, restraints, and helmet specifications and the effects of the impact with terrain at a high vertical velocity. No anomalies were noted.

The operator's communication center first attempted radio contact with the helicopter crew about 15 minutes after the accident and the paramedic made a mayday radio transmission about 22 minutes after the accident. Emergency response personnel located the helicopter about 41 minutes after the accident. The low-visibility weather conditions contributed to the delayed arrival of first responders.

The FAA did not require that the operator have an operational control center (OCC). Following the accident, the operator made communication center training and process improvements, including timely identification of an aircraft potentially in distress.


BRAINERD, Minnesota — The pilot’s spatial disorientation on a dark and foggy night was the probable cause of the fatal 2019 North Memorial Health helicopter crash at the Brainerd Lakes Regional Airport.

The National Transportation Safety Board issued its final report last month on the June 2019 crash that killed the pilot and a flight nurse while seriously injuring a flight paramedic. There was no mechanical failure reported.

It was just past 12:30 a.m. June 28 when pilot Tim McDonald initiated the instrument landing system in the Agusta medical helicopter. The three-person crew was returning from delivering a patient to North Memorial Medical Center in Robbinsdale and as they approached the airport, visibility was about a half-mile, deteriorating to a quarter-mile, according to the report. A quarter-mile visibility was the minimum distance approved by North Memorial Health for approaches at the time.

Following the accident, Josh Duda of Pillager, Minn., the flight paramedic seated in the left front seat, recalled the runway lights and surface were visible below a thin fog layer during the approach. As the helicopter approached the runway, he noticed clouds to the side and recalled McDonald stating the weather conditions were foggy and that a go-around was needed, the report stated.

Just before the helicopter lost control, McDonald declared a missed approach, likely due to the loss of visual contact with the runway. But a combination of factors caused an increase in torque and the helicopter accelerated into a spin before crashing near the runway.

“The dark night conditions at the rural airport resulted in little to no visual references during the pilot’s transition to landing and the attempted missed approach,” the report stated. “It is likely that the pilot became spatially disoriented, which led to the excessive pitch attitude, slow airspeed, his failure to recognize and arrest the right yaw, and the subsequent loss of control.”

Following the crash, North Memorial Health increased the minimum weather conditions required for pilots to conduct an instrument approach to a cloud ceiling of 400 feet above ground level and 1 mile visibility, the NTSB reported.

Although investigators state the helicopter was upright and nearly intact after the crash, they also report parts of it — including the main body and tail — “exhibited crushing consistent with a high velocity vertical descent.”

There was no evidence of a post-crash fire, but a portion of the ground was soaked in fuel.

An arc-shaped ground scar, consistent with a main rotor blade strike, was found to the left of the helicopter’s body. The outboard section of one tail rotor blade was found about 200 feet southwest of the helicopter. A 7-inch deep ground scar was located underneath the tail rotor and exhibited evidence of multiple tail rotor blade strikes.

McDonald and flight nurse Debra Schott died at the scene of the June 28 crash. Duda was taken to Essentia Health-St. Joseph’s Medical Center in Brainerd after the crash, and then to North Memorial in Robbinsdale.

McDonald, 44, a resident of Bloomington, was based at North Memorial Air Care’s facility in Siren, Wis., and is survived by his wife, Crystal and four children, according to a GoFundMe page set up in his honor. His obituary states he was a graduate of Gustavus Adolphus College and served as a helicopter pilot in the Army, completing two combat tours in Iraq before leaving to fulfill his dream of being a medevac pilot. He also earned his Master of Business Administration degree from Oklahoma State University.

Schott, 58, of Lester Prairie, Minn., graduated nursing school from Ridgewater College in Willmar, Minn., and earned her bachelor’s degree in nursing from Crow College, according to her obituary. She was first licensed as a practical nurse in 1980 at the age of 19 and received a license to work as a registered nurse in 1994. At the time of her death, she worked as a registered nurse at the Ridgeview Emergency Department, along with North Memorial Air Care.

Schott is survived by her husband, Gary, along with two children, two grandchildren, two stepchildren and seven step-grandchildren.

North Memorial Air Care has bases in Brainerd, Bemidji, Princeton, Redwood Falls and Lakeville.

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